Big Daddy 2 Rack BagUPC 859402006352 The Big Daddy 2 bike rack bag by BiKASE comes with a large main expandable compartment with a seam sealed liner, making the internal bag waterproof and drop down panniers on each side, adding extra storage for when needed! The Big Daddy 2 bike rack bag fits on all standard size rear bicycle racks using 4 straps to keep the bag tight and secure! RF seam sealed internal liner waterproof zipper on main storage compartment water bottle